Stroboscope



Dec. 19, 1933. E. FRlscHKNi-:CHT

STROBOSCOPE Filed March 17, 1931 6 Sheets-Sheet l INVENTOR Dec. 19, 1933.

E. FRlscHKNEcl-IT 1,940,411

srnooscor Filed March 17. 1931 6 Sheets-Sheet 2 INVENTOR BY o ATTORNEYS STROBOSCOPE Filed March 17 1-931 6 Sheets-Sheet 3 BY L.; ATroRNEYs wat/Ld' M6'- M Dec. 19, 1933. E. FmscHKNEcH-r STROBOSCOPE Filed March 17 1931 6 Sheets-Sheet 4 INVENTOR Zw es zlsck/zec BY u ATTORNEYS LUM). Mf- M Dec. 19, 1933. E. r-'RlscHKNEcl-rr swnososom Filed Maron 17. 1931 6 Sheets-Sheet 5 INVENTOR ElfzeS/zzlS/L/{f/zec BY la@ ATTORNEYS 0114"M] 'si M DCC- 19, 1933- a FRISCHKNECHT' 1,940,411

STROBOSCOPE Filed Maren 17, 19:51 e sheets-sheet e INVENT-oR BY /o ATTORNEYS UNITED STATES PATENT CFFICE STROBOSCOPE Ernest Frischknecht, Long Island City, N. Y., assigner to The Teleregister Corporation, New York, N. Y., a corporation of Delaware Application March 17, 1931. Serial No. 523,270 41 Claims. (Cl. F75- 183) This invention relates to a stroboscope. spring members 10 and ll, Fig. 5, secured to'a Among the objects of this invention is the block of insulating material 12 supported on the provision of improved mechanism for measurcabinet 1. The spring member 11 carries a ing the length of an electrical pulse, for measblock of insulating material 13 which cooperates uring the time required for a relay to close and with the cylinder 5. As the spring member 11, 60 open its contact, for obtaining a still view of duringthe rotation of cylinder 5', is permitted moving objects, for obtaining a slow movement to move toward the shaft 3 it carries the spring view of moving objects, for observing an object contact carrying member with it to disat any point in its movement, and for visually engage its contact from the contact on the sta- 10 indicating on a graph of the pulse operating tionary adjustable screw bolt or contact mem- 65 said object the point at which such object is ber 14 carried on a standard l5 secured to the viewed. cabinet 1, as shown at the right hand side of Other objects will be apparent from the fol- Fig. 5. As the cylinder moves the block 13 lowing description taken in connection with the away from the shaft 3 the member l1 is moved drawings, in which to the left, as shown at the left side in Fig. 5, m

Fig. 1 is a front view of the stroboscope permitting the contact member 10 to move to showing a suit-able control board; the left to engage the adjustable stationary con- Fig. 2 is a top plan view of the stroboscope; tact 14 at the left hand side of Fig. 5. As the Fig. 3 is a vertical section on the line 3-3 Contact c is closed it connects battery conof Fig. 2; nected to the spring contact member 10 across 75 Fig. 4 is a vertical section on the line 4-4 the adjustable contact 14 and the standard 15 of Fig. 2 with parts broken away; to a line leading to one of the pulse counting or l Fig. 5 is a vertical section on the line 5-5 .continuous pulse producing mechanisms, as will of Fig. 2; appearmore clearly in connection with the de- Fig. 6 shows the wiring diagram; scription of Fig. 6. As the members 10 and s0 Fig. 'I shows a computing chart; 11 assume the position shown at the right of Fig. 8 shows the graph of a pulse produced by Fig- 5 they Open the Circuit between battery and an oscillograph; the pulse counting or continuous pulseproducing Fig. 9 shows the slitted disk of the strobomechanisms. A scope; Two pairs of contacts a and c, and b and d 35 Fig. 10 shows diagrammatically the neon tube are preferably provided and One 0f these Pairs used in combination with an oscillograph; Vmay be used as a spare pair of contacts, or

Fig. 11 shows a. wiring diagram for testing pulses may go out over both pairs at the same the length of a pulse and for testing the time time to test two relays at the Same time.

required for a relay contact to close and to open; Well known mechanism may be provided to 90 Fig. 12 is a diagrammatic view showing the control the speed of the motor to rotate the control of the dial stroboscope, the observation cylinder at any desired number o rotations per stroboscope, and the stroboscope in the oscillosecond to produce any desired or required numgraph, bythe eccentric cam shown in Figs. 2, ber of pulses. The adjustable contact members 3 and 4; and 14 may be moved toward or away from the cylin- 95 Fig. 13 is' a side view of an indicator unit. der 5 to determine the length of the pulse from The mechanism shown in Figs. 1 to 5 includes the battery over the contact members 14 and 10 a cabinet 1, enclosing various switchmechafor any given speed of the motor. A relay may nisms controlled by manipulative means on a. be operated by the pulse produced by this mechpanel board 2. Mounted on top of the cabinet anism, and by observing on a dial later referred 100 1, shown in Fig. 2, is a motor Mo whose armato minimum and maximum lengths of pulses at ture shaft may be connected by a coupling and which the relay fails to function, and then takywheel to a shaft 3 which extends toward the ing the means between the minimum and maxileft, Fig. 2, and has secured thereto a. pair of mum length of pulses the proper operating pulse eccentric disks 4, Figs. 4 and 5, on which is for the relay may be determined. 105 mounted a cylinder 5 constituting a pulsing cam. As shown in Fig. 3, the shaft 3 is extended The shaft 3 is suitably supported on a bearing to the left, and at its left end carries a slitted 6 mounted on top of the -cabinet 1. Cooperating disk 19, Figs'. 3 and 9. The disk 19 is located with the cylinder 5 arecircuit closing contacts within a housing 20 which constitutes a beara, b, c and d, Fig. 2. Each contact comprises ing for the Shaft 3 and is provided with a foot 110 resting on the cabinet 1. The outer end of the housing 20 carries a graduated annular member 21 which preferably is provided with one hundred divisions, as shown in Fig. 1. The graduated member or dial 21 is provided with a set screw 22 which operates in a groove 23 in the housing 20 for permitting adjustment of the member 21 with respect to the housing for purposes later referred to, and for securing it in adjusted position.

Secured to the shaft 3 is an eccentric member 24 which counterbalances the pulsing cylinder or cam 5. Surrounding the member 24 is a cylindrical member 25 mounted concentrically with respect to the shaft 3 and secured to the disk 19. Coiled about the cylinder 25 and spaced therefrom and from the disk 19 and the housing 20 is a neon tube 26, as indicated in Fig. 3. 'Ihe outside surface of the cylinder 25 and the inside surface of the housing 20 are preferably coated with white paint to increase the illumination through the slit of the disk 19, as is obvious.

Supported on the right hand end of the housing 20, Fig. 3, is a worm gear 30 which is operated by worm 31 on a shaft 32 driven by a motor mo, Fig. 1. 'Ihe motor is preferably controlled in any suitable manner to operate forwardly or reversely.

The shaft 32 may be provided with a flywheel 33, Fig. 1, by means of which the shaft 32 may be turned by hand for purposes later set forth. The worm gear 30 carries a pair of contact members 34 and 35, Figs. 2, 3 and 4. The contact member 35 is provided with a block of insulating material 36 cooperating with the eccentrically mounted pulsing cylinder or cam 5. By means of the motor mo the switches 34 and 35 may be moved in a forward direction or in the reverse direction with respect to the direction of the movement of the cylinder 5 so that the circuit made by the contact members 34 and 35 will bear a variable timed relation to the circuits made by the contact members 10 and 14, Fig. 5. As shown in Fig. 3, the contact members 34 and 35 are provided with brushes cooperating with rings 36 and 37 carried by a block of insulating material secured to the housing 20. Cooperating With the rings 36 and 37 are brushes connected to incoming and outgoing circuit leads.

The operation and function of the mechanism so far described may be made clear-by reference to Fig. 6 which shows a wiring diagram for this mechanism. In this diagram the pulsing cam driving motor is indicated by Mo and the motor switch is indicated by B which connects the terminals of the motor to the terminals of a 48 volt battery. Below the motor Mo are indicated the pulsing contacts a, b and c, d. The neon tube is indicated below the switches at 26. On the left of Fig. 1 is shown a pulse counting controlling dial 40 which operates a contact arm 41, Fig. 6, with which are associated ten fixed contacts 1 to 10. On the right in Fig. 1 is shown another pulse counting controlling dial 401', the purpose of which will be brought out later.

The function of the pulse counting controlling dials 40 and 401 is to control the number of pulses sent out of the mechanism to a relay or relays to be tested. The arm 41 or 411' in contact with the contacts 1 to l0 controls the transmission of one to ten pulses by stopping the transmisison after one to ten pulses have been sent out. The circuits over arms 41 and 411' are completed by contact arms 42 and 42T operated by stepping magnets SM and SM1'.

The various manipulative means for controlling the mechanism shown in Fig. 6, are shown in Fig. 1. The motor is set in operation by throwing the switch B which, as shown in Fig. l, completes the circuit through the motor Mo over lines 45 and 46. As the motor is operated the pulsing cam 5 causes the various contacts a, b, c and d to close once during each rotation of the cylinder 5. As the contact b is closed it extends minus on the line 46 to the line 47 which extends to the upper contact of the switch SC which in one position, as indicated, controls the transmission f series of impulses and in the other position controls the transmission of continuous impulses. The line 47 also extends to the contacts on the right side of the switch SC (1 and 2) to control the simultaneous transmission of series of impulses or continuous impulses over outgoing lines with which the numerals 1 and 2 are associated at the right hand end of the figure. The line 47 also extends to a make contact 48 of the relay SP which is the start pulsing relay. When the switches SC and SC (1 and 2) are in the position shown in Figs. 1 and 6 and the contact 48 is open no impulses will be sent out over the outgoing lines with which the numeral 1 and the letter L are associated.

Minus on the line 46 is also extended across the contact a to the line 50 which extends to the normally open contact 48T on the relay SPr and to the switch SCr and to a contact on the right hand side of the switch SC (1 and 2). When these switches are in the normal position, as shown, no impulses can be sent out over the linesl with which the numeral 2 and the letter L are associated.

If it is desired to send out a series of one to ten pulses over either of the lines 1 and 2 the appropriate dial 40 or 40T is adjusted accordingly. If it is assumed that a relay to be tested is connected to line 1 and that it is desired to send a series of ve impulses to this relay the dial 40 will be moved to the 5 position to bring the arm 41, Fig. 6, into contact with the stationary contact 5. The switch C is moved to close its upper contacts. The switch SC is then moved to close the upper contact and the switch F is moved to close its upper contacts.

As the contact b closes and opens it sends pulses over the line 47 which now continue across the upper contact of the switch SC to line 5l which is the energizing lead of the stepping magnet SM. As this magnet operates it steps the arm 42 from its home position to a blank position and opens the circuit from battery across the arm 42 and line 52 of the relay SP which at its contact 48 connects the line 47 to the line 5l so that the stepping magnet SM will be operated each time an impulse is sent over the contact b as long as the relay SP remains deenergized.'

i As pulses are sent out over the contact b minus on the line 46 is connected across one of the upper contacts of the switch C to line 53 and continues over the contact d to line 54 and from line 54 over the contact 55 of relay SP and a break contact 56 of relay S to line 57 which is connected across one of the upper contacts of the switch F to the line 1. As the second pulse goes out over the contact b to step the arm 42 from the blank position to the one position a pulse over the contact d goes out over the line 1 to energize a relay to be tested.

As the third pulse goes out over the contact b to operate the arm 42 a second pulse goes out over the contact d and the line 1 to operate the relay to be tested. This operation continues until the arm 42 is stepped on to the contact 5 at which position it completes a circuit from battery across the contact 5, arm 41 and the coil of relay S. As this relay picks up it disconnects the line 54 from the line 5'7 which is connected across the switch F to the line 1 and thus discontinues pulsing over the line 1 to the relay. Five pulses have now been sent out to the relay and further closing of the contact d will be an idle operation. The pulses over the contact b continue to go out over the line 47 and over the contact 48 and line 51 to the stepping magnet SM causing the arm 42 to continue the stepping movement. It is assumed that the switch SC was brought back to normal after the rst operation of the stepping magnet. The stepping magnet will continue this operation until the arm 42 is moved over the ten contacts and the blank contact to the home position shown in Fig; 6, in which position battery is connected across the arm 42 to line 52 and across the coil of the relay SP to ground causing this relay to pick up and disconnect the line 47 at its contact 48 from the line 51 thus preventing further energization of the stepping magnet SM as the contact b closes and opens.

By means of the circuits described a series of five pulses have been sent out over the line 1 under control of the dial 40 and the parts have been restored to the position shown in Fig. 6.

As the relay S picked up during this operation it closed a holding,A circuit for itself :from battery over the operated make contact 60 of the relay SP and its own make contact 61 so that this relay remained energized as the arm 42 was moved offv contact 5 and remained energized until its holding circuit `vwas broken by opening of the contact 60 upon energization of the relay SP, as the arm 42 moved into its home position. As the relay SP is' energized it also opens the pulsing circuit for the line 1 at its contact 55.

If it is desired to send out successive series of any given number of pulses, for example 5 pulses in a series, the switch SC is moved as before to close its upper contacts and is left in that position. The mechanism will operate as before and the circuit will be made for the stepping magnet each time the contact b is closed so that energization and deenergization of the relay SP will have no effect on the operation of the stepping magnet SM. The arm 42 will be operated as before and as it moves from contact B to l, 2, 3, 4 and 5 a series of ve impulses will be Isent out over the line 1, the transmission of impulses ceasing as the arm 42 moves over the contact 5 thereby causing energization of the relay S which opens the outgoing circuit at its contact 56. The arm 42 continues` its movement into the home position but as its circuit is still closed vover the upper contact of the switch SC it will continue its movement and make another rotation, the relay SP closing the pulsing circuit at its contact 55 to start pulses for the line 1 and the relay S, later opening the pulsing circuit at its contact 56 to stop the transmission of pulses over the line 1 after ve pulses have been sent out. This operation will continue as long as the switch SC is in this position. By means of this mechanism spaced series of pulses may be sent out over the line 1 under control of the dial 40 and the switch SC. As is obvious, each series may contain from one to ten pulses the number of spaces between the seriesof pulses being equal to 13--the number of pulses sent. A

If it is desired to send continuous pulses over the line l the switch SC will be moved to close the lower contact to connect the line 54 directly to the line 57. In this case the stepping magnet SM will not be energized and the relay SP will remain energized so that the pulses will continue as long as the switch SC remains in this operated position.

If it is desired to send pulses out on the line 2 to a relay to be tested the dial 40T is set over the numeral designating the number of pulses desired and the switch SCT is moved to close its upper contact. As the contact a closes it extends minus on line 46 over line 50 and the upper contact of the switch SCT to line 62 and the coil of -the stepping magnet SMT to ground causing this magnet to step the arm 42T clockwise to the blank position which opens the circuit for the relay SPT which at its contact 48T connects the line 50 to the line 62 so that the stepping magnet SMT will be energized in the event that the switch SCT has been brought back to normal position, as long as the relay SPTV remains deenergized.

If it is desired to send a series of iive impulses out over line2 the dial 40T will be moved over the number 5 so as to position the arm 41T over the contact 5. Y

The switch C connected minus on the line 46 from the 48 volt battery over one of its upper contacts to line 63. The minus on line 63 is extended across the contact c to the line 64 which is connected across the contact 55T of relay SPT and the contact 56T of relay ST to line 65 which is extended across one of the upper contacts of the switch F to the line 2.

As the arm 42T is moved from the home position to the blank position it causes the relay SPT to be deenergized and to prepare a pulsing circuit to the line 2 at its contact 55T. When the stepping magnet is operated again to` move the arm 42T from the blank position to the one posi-y tion a pulse is sent out over the contact, c, line 64, line 65 and line 2 to the relay to be tested. This operation continues until the arm 42T moves over the contact 5 which completes the circuit for the relay ST which operates and opens the pulsing circuit at its contact 56T. The relay S1' at its contact 61T closes a holding circuit for itself over a contact 60T of relay SPT so that the pulsing circuit will remain open as long as the relay SPT remains energized, that is, until the arm 42T has made a complete rotation into the position shown in Fig. 6.

If it is desired to send a succession of series of pulses over the line 2 the switch SCT will be left in its operated position in which it connects the line 50 to the line 62.

If it is desired to send continuous pulses over the line 2 the switch SCT will be moved to close its lower contact to connect the line 64 directly to the line 65 so that the pulses over the line 2 will not be dependent upon the operation of the relays SPT and ST.

It is obvious, of course, that by adjusting the dials 40 and 40T and by setting the switches SC and SCT a single series of pulses or a succession of series of pulses or continuous pulses will be sent out over the lines 1 and 2 simultaneously. It is obvious, of course, that the number of pulses sent out over the line 1 may .be differentv from the number of pulses sent out over the line 2 so that two relays may be tested simultaneously under different conditions.

For the purpose of sending out series of pulses or continuous pulses over both lines 1 and 2 a switch SC (l and 2) may be provided. When this switch is moved so as to close the left hand contacts it will connect the line 54 to the line 5'! and the line 64 to the line 65 thus causing continuous impulses to go out over lines 1 and 2.

When the switch SC (1 and 2) is moved so as to close the right hand contacts it connects the line 47 to 51 and the line 50 tothe line 62 so that the impulses produced by the contacts b and a will cause the stepping magnets SM and SM1 to operate. If the dials 40 and 40r have been set, for example to 4 and 6 respectively, a series of four impulses will go out over the line 1 and a series of six impulses willgo out over the line 2 and but `one series of impulses will go out over these linesif the switch SC(1, and 2) is moved back to normal position before the respective number of impulses have been sent out. If the switch is left in this operated position successive series of four impulses will go out over the line 1 and a successive series of six impulses will go out over the line 2. and this will continue until the switch SC (1 and 2) has been moved back into its home position.

If it is desired to send impulses from the 150 volt battery the switch C ismoved so as to close the lower contacts and apply positive battery to the line 53 and negative battery to the line 63 so that positive impulses of 150 volts may be sent out ;over the line 1 under control of the left hand 'dial mechanism 40 and negative impulses of 150 volts may be sent out over the line 2 under control of the right hand dial 401'.

If it is desired to test a polarized relay, positive and negative impulses may be sent to this relay over the line L when the, switch F is moved so as to close its lower contacts and connect the lines 57 and 65 to the line L.

If it is desired to measure the length of a pulse going out to a relay to be tested and the control over the pulses is set up in the mechanism on the left by means of the dial 40 and switch SC, then the clip 38, Fig. 6, is connected to the far side of the switch d, for example to the standard 15 on the right hand side of Fig. 5. Each time that a pulse is sent out over the line 54 a pulse will continue over the clip 38, the neon intensity control resistance NI, the primary coil P, over line 70, switch E, which now has been moved to close its upper contacts, and arm '71 to the positive side of the 48 volt battery, if the arm is positioned over the second contact in Fig. 6. As the pulse builds up it induces a current in the secndary coil S, which operates the neon light 26, Figs. 6 and 3. This causes a ash to be observed through a slit in the disk 19, Figs. 1 and 9. As the pulse ceases it causes another flash of the neon light 26 observable through the slit in the disk 19. By means of this mechanism the neon light is energized at the beginning and end of the pulse so that the length of the pulse can be measured in terms of 100%, by observing where these ashes occur, and readingor calculating the diierence in percentage. The arm 7l is moved over the proper positive or negative contact to complete the circuit through the neon tube, as is understood.

In order to determine which ot the flashes represents the beginning of the pulse the switch E, Fig. 6, is moved to close its lower contacts so that the circuit over the coil P will continue over a contact 72 operated by this coil and over the switch E and arm '71 to the respective contact, etc. As the pulse passes over coil P it causes the contact '72 to vibrate which causes the neon light 26 to turn off and on in rapid succession. The effect of this observed from the front of the machine is a succession of lines following the first line of light produced through the slit at the beginning of the pulse or at make time of a relay to be tested.

By means of the adjustable contacts 14, Fig. 5, it is possible to shorten the length of the pulses until they are too short to operate the relay and to measure the length of such pulses. It is also possible to adjust the pulse to a length long enough to make the relay fail and to read or calculate the length of this pulse. By taking the mean between the length of the short and long pulses a satisfactory operating pulse for the relay mayA be calculated. The screws 14 will be adjusted until the flashes of the neon light in connection with the graduated scale 21 indicate that the pulse delivered to the relay is of the length determined by the above calculation.

Ii it is desired to find the length of time required for a relay to operate and to release for a given length pulse the relay will be operated and the disk 2l will be moved until the zero position is opposite the flash which indicates the beginning of a pulse. The clip 38, Figs. 6 and 11, is then shifted from the post 1, Fig. 1l, to which it was clipped to measure the length of the pulses, to post 2 so that the neon light will be controlled by a circuit from battery over the contact 74 of relay R to be tested. When the contact 74 is closed the neon light 26 will flash and by rotating the member on the`graduated ring 21 opposite the flash the length of time required to close the contact may be calculated directly. Each time that the contact '14 is opened the neon light will again flash and by observing the point on the scale opposite this ash the time of release of the relay may be calculated.

By referring to Fig. 7 it may be seen that the length of the pulse may be indicated by the inner partial circle bearing the legend Generation and the point at which the contact closes and opens may be indicated by the second circle from the center bearing the legend Relay 1 Contact, and that the timev required to close a contact may be directly read or calculated from this chart which, as shown, is 5% in the assumed case, and the time for release of the relay is 20% in the assumed case. The

lrelay tested may operate another relay the operation of which may be represented by the third circle bearing the legend Relay 2 (Operated from Relay 1). It may then be calculated as to how `long it took the relay 2 to pick up after the relay 1 picked up and after the pulse was completed, and how long it took the relay 2 to release after the rst relay released and after the pulse ceased.

For certain testing operations it is desirable to have the neon light ilash but once for each pulse sent out to the relay to be tested. For this purpose I have provided contacts 34 and 35, Figs. 2, 3 and 4, which apply a plus from a 2 to 6 volt battery to the transformer as indicated in Fig. 12, the secondary coil oiv which may be connected by a switch arm 75 -to a neon tube associated with the dial mechanism such as shown in the preceding figures or to an observation neon tube 76 or tothe neon tube 77 in the oscillograph, see also Fig. 10. As the pulses are sent out to the relay to be tested the contacts 34 and 35 are closed but the voltage is insufficient to cause the neon tube to flash at the beginning of the pulse. As the contacts 34 and 35'remain closed for a certain length of time a sulilcient amount of v current will build up to cause the neon tube to flash when these contacts are opened. By means of this mechanism one flash will be produced for every impulse sent out.

By turning the hand wheel 33, Fig. l,` the worm wheel 30 andcontacts 34 and 35 may be rotated so that-this ash will occur at different times with respect to the outgoing pulse. If the arm 75, Fig. 12, is moved over contact 2 to energize the observation neon tube, which is preferably portable and may be caused to flash on the contact 74 of the relay R, Fig. 11, it will be noticed that by moving the contacts 34 and 35 that the neon tube may be caused to flash at any point of the contact 74 in any of its positions causing this contact' to appear to be at rest in such posi-V tion. By means of this construction a still view of the contact may be had in any of its positions and its operation may be observed. After a still view of the contact or armature at any particular point of its movements has been observed the switch arm 75, Fig. 12, may be moved over contact 1 or 3 to energize the neon tube 26 or 77, Fig. l2, which causes a llash to be made at the time that the contact reaches the particular position observed. The flash strikes the time mirror 78 of an oscillograph and is reflected on a screen on which appears a curve indicating the pulse transmitted to the relay, such curve being made by the usual time mirror before referred to and an amplitude mirror 79 whose position is controlled by the outgoing pulse, as is well understood. By means of this connection a vertical line will cross the graph of the pulse curve, Fig. 8, at a point corresponding to the part of the pulse corresponding in time to the position of the contact 74 observed in the still view. This at once gives a visual relation between the beginning of a pulse and the position of the contact 74.

In Fig. 12 is shown an indicator unit such as is used in well known teleregister systems which comprises an operating magnet 80 which cooperates with an armature 81 integral with an operating fork 82 which cooperates with a ratchet disk 83 on an indicator drum 84, the fork being operated downwardly upon energization ofA the magnet and being pulled upwardly by a spring 85. Secured to the end of the indicating drum is a. ratchet disk 86 provided with twenty-two holes, that is, twice the number of the positions of the indicator with which cooperates a spring retaining finger' 87. The magnet of the indicator unit may be connected to terminal 1, Fig. 6, and the length of the pulse which may be 48 or 150 volts, etc. may be adjusted until a `maximum and minimum operating pulse is determined after which the pulse may be adjusted to the best operating length. If it is desired to observe the operation of any part of this mechanism, for example, the fork, the observation neon light 76, Fig. l2, is caused to ash on the operating fork at the desired time by the adjustment of the contacts 34 and 35, Figs..3 and 4. After a still view is obtained of the fork or any part of the fork at the desired point of operation the arm 75, Fig. 2, is moved over contact l or 3 and the time relation between the point at which this observation is made and the beginning of the pulse may be observed on the oscillograph in Figs. 8 and l0. If desired, the neon tube associated with the dial construction in Figs. 1, 2 and 3 may be energized by moving the arm over the Contact l, Fig. 12, and the position of the flash may be read on the graduated member 21, Fig. 3, and noted on the chart in Fig. 'I from which the exact time between the starting of the pulse and the time at which the operation is observed may be calculated.

Ii desired, a slow 4motion picture of the fork may be obtained by closing the switch for the motor mo, Figs. 1 and 2, by means by which the contacts 34 and 35 may be revolved forwardly at a slow speed so as to cause the neon tube to flash on the fork at a slightly later time during each successive operation of the fork. This will cause the fork to appear to travel-forwardly very slowly. By mechanism well known the direction of the rotation of the motor may be changed and a slow motion picture of the fork appearing to move in the reverse direction may be observed.

Continuous minus from the 48 volt battery may be applied to line l, Fig. 6, by closing the switch B, operating the switch C to close its upper contacts, operating a switch DC to connect line 53 to 54 directly, operating the switch SC to connect the line 54 to 57, and operating switch F to connect line 57 to the line 1. Similarly, by operating switch DCr and operating switch SCT to connect line 63 to 64 and line 64 to 65, minus from battery may be applied to line 2.

By operating switch C to close its lower contacts, plus from the 150 volt battery may be applied to line 1 and minus from battery may be ,applied to line 2.

By operating the switch F to close its lower contacts, single series of pulses, spaced series of pulses, continuous pulses, and direct current from either battery may be applied to line L for testing polarized relays.

As may be Well understood, two neon tubes 26 may be employed, one of which may be operated from post 1, Fig. v11, and the other from post 2. Simultaneous operation of these tubes will cause a flash to appear at the beginning of a pulse, a second flash at the closing of contact 74, a third flash as the impulse ceases a fourth flash as the contact 74 opens. In. slowto-release relays the complete time between the first and fourth flashes may be lmore than 100% In this -event and for convenience in distinguishing generally between the various flashes,-

the additional tube 26 may be filled with a gas, such as mercury vapor, to emit a light of different color. Y

It is also to be noted that chattering of a contact either as it opens or closes may be observed by a seriesof-flashes similar to those produced when theiscillating contact is used to produce a series 'of flashes to determine which of a pair of flashes is produced at the beginning ci a pulse.

It may also be found desirable to connect a condenser and resistance in parallel in the circuit of the neon tube, to produce a flash only at the beginning of a pulse.

While the invention has been described with reference to a specific embodiment, it is obvious 'that various changes may be made without departing from' the spirit of this invention and that it is to be understood that the terms employed in the claims are terms of description rather than of limitation.

What I claim is:

l. The combination of an adjustable pulsing mechanism comprising a rotatable cam, means for rotating said cam at a constant speed, a movable circuit closing contact operable by said cam, an adjustable stationary contact cooperable with said movable Contact for controlling the length of a pulse, a slitted disk rotatable with said cam, a neon tube, means `for operating said tube as the circuit is made and broken by said contacts, and a graduated circular scale associated with said disk.

2. The combination of an adjustable pulsing mechanism comprising a rotatable cam, a shaft supporting said cam, means for rotating said shaft at a constant speed, a movable Ycircuit closing contact operable by said cam, an adjustable stationary contact cooperable With said movable contact for controlling the length of a pulse, a slitted disk mounted xedly on said shaft, a neon tube, means for operating said tube as the circuit is made and broken through said contacts, and a graduated circular scale associated with said disk. l

3. The combination of an adjustable pulsing mechanism comprising a rotatable cam, means for rotating said cam at a constant speed, a movable circuit closing contact operable by said cam, an adjustable stationary contact cooperable with said movable contact for controlling the length of a pulse, a slitted disk rotatable with said cam, a neon tube, means for operating said tube as the circuit is made and broken by said contacts, a graduated circular scale associated with said disk, and means for operating a relay to betested by the circuit made through said contacts.

4. The combination of an adjustable pulsing mechanism comprising a rotatable cam, means for rotating said Acam at a constant speed, a movable circuit closing contact operable by said cam, an adjustable stationary contact cooperable with said movable contact for controlling the length of a pulse, means for connecting a relay to be tested in the circuit of said contacts, a second pair of contacts cooperating with said cam, means for adjusting said contacts circumferentially with respect to said cam, a neon tube, and means for operating said tube by the circuit made across the latter pair of contacts as the circuit is broken.

5. The combination of an adjustable pulsing mechanism comprising a rotatable cam, means for rotating said cam at a constant speed, a movable circuit closing contact operable by said cam, an adjustable stationary contact cooperable with said movable contact for controlling the length of a pulse, means for connecting a relay to be tested in the circuit of said contacts, a second pair of contacts cooperating with said cam, means foradjusting said contacts circumierentially with respect to said cam, a neon tube, means for operating said tube by the circuit made across the latter pair of contacts as the circuit is broken, and manipulative means for adjusting said latter pair of contacts for obtaining a still View of the relay at any point of its movement.

6. The combination of an adjustable pulsing mechanism comprising a rotatable cam, means for rotating said cam at a constant speed, -a movable circuit closing contact operable by said cam, an adjustable stationary contact cooperable with said movable contact for controlling the length of a pulse. means for connecting a relay to be tested in the circuit of said contacts, a second pair of contacts cooperating with said cam, means for adjusting said contacts circumferentially with respect to said cam, a neon tube, and a motor for revolving said latter pair of contacts with the cam at any desired speed to obtain a slow motion view of the relay to be tested.

7. The combination of a mechanism for producing a desired constant number of pulses to operate Ia relay to be tested, means for controlling the transmission of a single series of a variable number of pulses, means for controlling the transmission of an indefinite number of series of variable pulses, and means for controlling the transmission of a continuous series of pulses.

8. The combination of a mechanism for producing a desired constant number of pulses to operate a relay to be tested, two sets of means `for controlling the transmission of a single series of a variable number of pulses, two sets of means for controlling the transmission of an indefinite number of series of variable pulses, two sets of means for controlling the transmission of a continuous series of pulses, said two sets of means permitting two relays to be tested simultaneously.

9. The combination of a mechanism for producing a desired constant number of pulses to operate a relay to be tested, two sets of means for controlling the transmission of a single series of a variable number of pulses, two sets of means for controlling the transmission of an indefinite number of series of variable pulses, two sets of means for controlling the transmission of a continuous series of pulses, said two sets of means permitting two relays to be tested simultaneously, a plurality of electrical sources of different voltage, a motor operated by one of said sources for operating said pulse producing mechanism, and means for connecting saidpulse producing mechanism to either source.

10, The combination of a mechanism for producing a desired constant number of pulses to operate a relay to be tested, two sets of means for controlling the transmission of a single series of a'variable number of pulses, two sets of means for controlling the transmission of an indefinite number of series of variable pulses, two sets of means for controlling the transmission of a continuous series of pulses, said two sets of means permitting two relays to be tested simultaneously, a plurality of electrical sources of different voltage, a motor operated by one of said sources for operating said pulse producing mechanism, means for connecting the same side of one of said sources to the pulse producing mechanism to send out pulses of the same polarity under control of said two sets of means, and means for connecting said other source to the pulsing mechanism to transmit pulses of different polarities.

11. The combination of a pulse producing mechanism, an oscillograph comprising the usual time mirror and amplitude mirror for producing on a screen a curve of a pulse, means for operating a relay to be tested by said pulse, a neon tube, a second pulse producing device operable in adjustable timed relation to said first pulse producing device for operating said neon tube at any point in the duration of said first pulse for producing a still view of the armature of the relay to be tested at any point of its movement, means for operating said neon tube as the energizing pulse ceases, a second neon tube, andv means for energizing said second neon tube by said second pulse to project a line of light against the time mirror to be reflected across said curve `to obtain a visual relation between the time ofthe amplitude curve and the point at which the armature is observed.

12. The combination of a rotatable pulsing cam, a slitted disk rotatable with the cam, a neon tube associated with said disk, means for operating said neon tube, a relay to be tested by the pulse produced by said pulsing cam, a graduated dial associated with said slitted disk, and means for adjusting said dial to move the Zero o the dial opposite the line produced by the neon tube and the disk denoting the beginning of the pulse.

13'. The combination of a rotatable pulsing cam, a slitted disk rotatable with the cam, a neon tube associated with said disk, means for operating said neon tube, a relay to be tested by the pulse produced by said pulsing cam, a graduated dial associated with said slitted disk, means for adjusting said dial to move the zero ofthe dial opposite the line produced by the neon tube and the disk denoting the beginning of the pulse, means for energizing said neon tube at the beginning and end of the pulse, and a vibrator for causing said neon tube to ash a plurality of times during the continuation of the pulse for the purposerof determining which of the flashes indicates the beginning and the end of the pulse.

14. The combination of a lamp, pulsing mechanism for transmitting spaced pulses of diierent lengths across the circuit of said lamp, and means cooperating with said lamp for measuring the length of pulses transmitted.

15. The combination of a neon tube, pulsing mechanism for transmitting spaced pulses of different lengths over lthe circuit of said neon tube, means for causing said neon tube to light as the circuit is made and broken, and means cooperating with said neon tube for measuring the length of said pulses.

16. The combination of a neon tube, pulsing mechanism for transmitting pulses of different lengths over the circuit of said neon tube, means for causing said neon tube to light as the circuit is made and broken, a scale cooperating with said neon tube, and means for causing a light from said neon tube to light different parts of said scale to indicate by the intercepted portion of said scale the length of the pulse over the circuit of said neon tube.

17. The combination of a lamp, pulsing mechanism for transmitting pulses of diierent lengths across the circuit of said lamp, means cooperating with said lamp for measuring the length of pulses transmitted, and means causing a relay to be tested, to be operated by the pulses transmitted over said circuit.

18. The combination of mechanism for producing pulses of different. lengths, means for connecting a relay to be tested in a circuit over which said pulses are transmitted, means for transmitting pulses over a second circuit subsequently and in adjustable varied time relation to said rst pulses, a neon -tube in said second circuit, and means for operating said neon tube at the termination of each of said second pulses.

19. The combination of mechanism for producing pulses of different lengths, means for connecting a relay to be tested in a circuit over which said pulses are transmitted, means for transmitting pulses over a second circuit subsequently and in adjustable varied time relation to said first pulses, a lamp in said second circuit, and means for operating said lamp at the termination of each of said second pulses.

20. The combination of mechanism for transmitting pulses of variable lengths over the coil of a relay to be tested, and manipulative controlled means for controlling the automatic successive transmission of a continuous series of a variable number of pulses.

21. Thecombination of mechanism for transmitting pulses of variable lengths over the coil of a relay to be tested, and manipulative means for controlling the automatic successive transission of a plurality of spaced series of pulses each containing a predetermined number of pulses.

22. The combination of mechanism for transmitting pulses of variable lengths over the coil of a relay to be tested, manipulative controlled means for controlling the automatic successive transmission of a continuous series of a variable number of pulses, of one of a plurality of different voltages.

23. The combination of mechanism for transmitting pulses of variable lengths over the coil of a relay to be tested, manipulative controlled means for controlling the automatic successive transmission of a continuous series of a variable number of pulses, of either polarity.

24. The combination of pulsing mechanism for transmitting pulses over the coil of a relay to be tested, a neon tube, means forboperating said neon tube at the beginning and end of a pulse, and a vibrator for causing said neon tube to flash a plurality of times during the continuance of the pulse.

25. The combination of means for transmitting pulses of variable lengths over the coil of a relay to be tested, means for-measuring the length of said pulses, and means for measuring the operating time and release time of the relay.

26. The combination of means for transmitting pulses of variable lengths over the coil of a relay to be tested, and means for graphically indicating the value of the pulse at the time the relay is fully operated.

27. The combination of means for transmitting pulses of variable lengths over the coil of a relay to be tested, means for obtaining a still view of the movable armature at any point of its movement, and means for graphically indicating the 130 point of the pulse at which the relay armature is observed.

28. The combination of means for transmitting pulses of variable lengths over the coil of a relay to be tested, means for obtaining a still view of 135 the movable armature at any point of its movement, and means for indicating on a scale the point of the pulse at which the relay armature is observed.

29. The combination of means for transmitting 140 pulses over the coil of a relay to be tested, a neon of the relay, and means for causing said neon pulse and at the time the armature of the relay opens.

32. The combination of mechanism for producing pulses, means for connecting a relay to,

be tested in a circuit over which said pulses are transmitted, means for transmitting pulses over a second circuit subsequently and in adjustable varied time relation to said r'st pulses, a lamp in said second circuit, and means for operating said lamp at the termination of each of sa-id second pulses.

33. The combination of a lamp, pulsing mechanism for transmitting spaced pulses across the circuit of said lamp, and mea-ns cooperating with said lamp for measuring the length of pulses transmitted.

34. The combination of a neon tube, pulsing mechanism for transmittingispaced pulses over the circuit of said neon tube, means for causing said neon tube to light as the circuit is made and broken, and means cooperating with said leon tube for measuring the length of said pulses.

35` The combination of mechanism for r.transmitting pulses over the coil of a relay to be tested, and manipulative controlled means for controlling the automatic successive transmission of a continuous series of a variable number of pulses.

36. 'I'he combination of mechanism for transmitting pulses over the coil of a relay to be' tested, and manipulative means for controlling the automatic successive-transmission of a plurality of spaced series of pulses each containing a `predetermined number of pulses.

37. The combination of mechanism for transmitting pulses over the coil. of a relay to be tested, manipulative controlled means for controlling the automatic successive transmission of a continuous series of a variable number of pulses, of one of a plurality of different voltages.

38. The combination of mechanism for transmitting pulses over the coil of a relay to be tested, manipulative controlled means for controlling the automatic successive transmission of a continuous series of a variable number of pulses, of either polarity. y

39. The combination of means for transmiting pulses over the coil of a relay to be tested, and means for graphically indicating the value of the pulse at the time the relay is fully operated.

40. The combination of means for transmitting pulses over the coil of a relay to be tested, means for obtaining a still view of the movable armature at any point of itsmovement,Y and means for graphically indicating the point of the pulse at which the relayarmature is observed..

41. The combination of means for transmitting pulses over the coil of a relay to be tested, means for obtaining a still view of the movable armature at any point of its movement, and means for indicating on a scale the point of the pulse at which the relay armature is observed.

ERNEST FRISCHKNECHT. 

